WO1986006587A1

WO1986006587A1 - The processing of poultry

Info

Publication number: WO1986006587A1
Application number: PCT/AU1986/000124
Authority: WO
Inventors: Robert W. Pinkerton
Original assignee: Golden Poultry Farming Industries Limited
Priority date: 1985-05-06
Filing date: 1986-05-06
Publication date: 1986-11-20

Abstract

A method and apparatus for removing neck skins from poultry. Each bird is hung on a shackle (11) from an overhead conveyor (10), a load cell weights each bird as it passes through a weighing station, a computer receives a signal representing the weight and position of each bird. A cutting station (50) is positioned in the conveyor line and includes a displaceable cutting blade. The computer sends a signal to the cutting station to displace the cutting blade to a position across the path of the neck skins to remove the neck skins of a certain number of birds of a predetermined weight.

Description

THE PROCESSING OF POULTRY This invention relates to the processing of poultry and in particular relates to a method and apparatus for removing the neck skin from poultry.

The breeding and processing of poultry has become highly automated. There is ..an extensive range of automatic equipment that kills, plucks and prepares poultry ready for the user.

Poultry and especially chickens have comparatively long necks. During the processing of the chicken, the head and neck are removed leaving a substantial mass of outer neck

£?-=^' skin. This skin can weigh between 40 and 50 grams and since chickens are sold by weight, the neck skin inherently becomes a component of the overall cost of the chicken.

Chicken processors frequently supply to a variety of customers. Some customers, particularly the purchasers of large quantities of chicken sections do not require the neck skin and therefore demand that the skin be removed.

To date removal of the skin has proved a labour intensive and expensive exercise because, as processors supply to many markets, not all require the skin to be removed and thus the processor has the problem of selecting which chickens to remove the skins and then removing the skins.

This invention relates to a method and apparatus that overcomes this problem in a simple manner whilst using much of pre-existing automated equipment.

According to one aspect of the present invention there is provided a method of selectively removing neck skins from poultry comprising hanging each bird upside-down from a weighing shackle forming part of an overhead conveyor, electrically weighing each bird by weighing the hanging bird and shackle, feeding a signal responsive to the weight and position of the bird into a computer, conveying each bird past a cutting station, and programming the computer to feed a signal to means to actuate a cutting blade to remove the neck skins of a preselected number of birds of certain weights.

The computer is programmed to ensure that a certain number of poultry within a particular range of weights have the neck skin removed.

According to a further aspect of the present invention there is provided apparatus for selectively removing neck skins from poultry comprising an overhead conveyor carrying a plurality of spaced weighing shackles, a bird being arranged to be hung from each shackle, means to weigh each bird whilst hanging from the shackle, means to send a signal responsive to the weight and position of the bird, a computer programmed to store the signal responsive to the weight and position of each bird, and a cutting blade assembly displaceable to a position across the path of the neck skins of the poultry as they travel along the conveyor, whereby in use the computer sends a signal to the cutting blade assembly to displace said assembly to the cutting position as a bird of preselected weight reaches the cutting station.

The cutting blade assembly preferably comprises a rotatable cutting blade and means to displace the blade from a non cutting position to the cutting position across the path of the neck skins.

One embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a side-on view of part of a conveyor line for the processing of chickens,

Figure 2 is a sectional view taken along the lines 2-2 Figure 1,

Figure 3 is a sectional view taken along the lines 3-3 of Figure 1,

Figure 4 is a logic flow chart of the operation of the conveyor line.

Figure 5 is a schematic view of the physical arrangement of components of the conveyor line, Figure 6 is a schematic view of the electrical interconnection of the components,

Figure 7 is a schematic view of the physical arrangement of a cutter for the neck skins of chickens,

Figure 8 (divided into parts) is a circuit diagram of a relay card forming part of the conveyor system, and

Figure 9 (divided into parts) is a circuit diagram of a shift register card forming part of the conveyor system.

Figures 1 to 3 of the accompanying drawings illustrate part of an automated line for the processing of chickens. Generally chickens are sold by weight and a numbering system is used to indicate particular weights, in any batch of birds, there is a considerable variation in the weights of individual birds. Chicken producers also supply to a variety of customers and these customers demand chickens in a variety of forms. For instance, some customers demand whole chickens of a particular weight, others require chicken pieces and some customers require boned chickens. Thus, in an automated processing line, it is very desirable for the producer to have a number of bins or drops, each containing processed birds of a particular weight. In the processing system described herein, the birds are first killed, plucked and trimmed. The trimming operation comprises removal of the head, neck and feet, the internal organs or waste are also removed from the chicken. As shown in Figure 1 each bird 20 is then hung by one shin bone 21 from a shackle 11 forming one of a plurality of equally spaced shackles that form part of an overhead conveyor assembly 10. The conveyor assembly 10 includes a weighing station (not shown) that comprises at least a pair of strain gauges or weight cells positioned on the conveyor rail 15. .As each shackle and bird passes along the rail between the strain gauges an electric signal responsive to the weight of the bird and the shackle is transmitted by the strain gauges. Since the weight of the shackle is already known, the weight of the bird can thus be computed from this signal. .A computer (not shown) is coupled to the strain gauges and records a signal responsive to the weight of the bird as well as a signal that tells the computer which shackle is being weighed. Thus at any one time, the computer has sufficient information to know the weight of a particular bird and its position on the conveyor. The user of the assembly may thus program the computer to ensure that birds of a particular weight are deposited at a particular drop. In the system of a preferred embodiment described herein, two drops are positioned in a boning room and some drops are marked KFC which means that the bins are then transferred to a piecing machine. Other drops are marked TAF indicating that the bins are for takeaway food stores. Of the remaining drops, the birds are packaged, numbered by weight and frozen for retail sale.

The overhead conveyor and weighing equipment including_, the computer are known proprietary items marked under the Trade Mark CHICKWAY by a British company Chickway Company Limited. The present invention has been developed by using the information stored in the computer to actuate a cutting station 50 to cause removal of the neck skins of certain birds falling within a particular weight range. The cutting station 50 is named the Neck Flap Cutter and referred to as N.F.C. herein. As shown in Figures 1 to 3 the cutting station 50 incorporates a horizontally mounted rotatable cutting blade 51 driven by an electric motor 52. The electric motor and cutting blade are mounted on a support means 53 that is in turn mounted for pivotal movement about an arm 54 coupled to the frame of the assembly 56. The arm 54 pivots about a pivot point 55. Suitable actuating means in the form -of a pneumatic or hydraulic ram 59 is positioned between the arm and the frame to cause the arm to be displaceable from a first position illustrated by the letter A in Figure 2 in which the periphery of the cutting blade is displaced from the path of the neck skins of the chickens to a second position marked B on Figure 2 in which the cutting blade crosses the path of the necks of the chickens as they move past the blade on the conveyor. A nylon guide 60 having a longitudinal slot 61 coincident of with the plane of the cutting blade is positioned o'pposite the extreme position of the cutting blade adjacent the path of the necks of the chickens to ensure against displacement of the necks away from the blade. As can be seem from Figures 2 and 3 the blade in its cutting position extends into the slot 61 in the nylon guide 60. The conveyor also includes guide means 70 and 71 that extend on each side of the neck of the birds, the guide means are inclined upwardly as shown in Figure 1 and define a gap 72 therebetween through which neck of the birds pass as they are conveyed through the cutting station. To remove the neck skins, the ram 59 displaces the electric motor 52 and cutting blade 51 into the position B causing the rotating cutting blade to cut off the neck at the desired height. Although not shown in detail in the drawings means is provided to adjust the height of the cutting means so that the desired amount of neck skin is removed.

In an automated processing plant of this kind, the birds vary in weight and size. Customers who desire the neck skin to be removed also request birds falling within a particular range of weights. In any particular line of birds there will be a large discrepancy between the weights of the birds. It is for this reason that the computer is used to determine the weight and position of any particular bird.

In this invention the computer is programmed to note the number of birds that are required by a particular customer requiring removal of the neck skin and to ensure that a signal reflecting this number is transmitted to the actuating means to ensure that when a bird of a particular weight in is the cutting station, the ram is actuated to cause the blade to remove the neck skin. In this manner, only the birds of a predetermined range of weights are cut and only a predetermined number of birds have the neck skins cut.

The shackles also include means to effect release of the birds and suitable hoppers may be placed around the conveyor line to ensure that birds of particular weights are released at 'certain times. These points of release are referred to as drops. In this manner, all the birds of a certain weight that have had their neck skins removed may be released at a particular drop or drops. As mentioned earlier in the specification the invention is an adaption of a proprietary computerized weighing and conveying assembly manufactured by a British company Chickway Company Limited and known as a CHICKWAY 2.2. The adaption known as the Neck Flap Cutter (N.F.C.) has been custom designed to run with the CHICKWAY processing unit. The computer of the CHICKWAY unit has been used to carry out the control of the N.F.C. The logic flow chart is illustrated in Figure 4. The following description with reference to Figures

5 to 9 is adapted from the manual accompanying the modifications to the CHICKWAY unit.

The Neck Flap Cutter (N.F.C.) has been custom designed to run with a chicken processing unit, in a manner that does not interfere with the central control system. The N.F.C. system consists of a Rack Housing, Relay Cards, Shift Register Cards and a Regulated Power Supply.

The main task of the N.F.C. unit is to take- "drop" signals from the processing unit, in this case a Chickway 2.2 (C.W2.2) (which represents a chicken that has to have its neckflap removed) and shift it electrically, in synchronism with the line until the bird is in position to have its neck cut, whereby a signal is given to operate a cutter solenoid. Continuing on from there, the signal is electrically shifted, again in synchronism with the line, until it has reached the drop position, where a signal will be given to operate a drop solenoid and drop the bird in its correct bin. The N.F.C. requires the drop signals that come from the CW2.2 to occur before the cutter position so that the control actions of cutting and dropping may be accurately predicted. This means that the CW2.2 must produce the drop signals before the cutter and before the physical drop positions. To achieve this, a new CW2.2 sensor is positioned on the line. The relay card switches this sensor to the CW2.2 when the N.F.C. system is activated. The new sensor is positioned so that the last drop in that sensors control range occurs at least 5 or so shackles before the cutter.

The relay cards enable a changeover from a straight CW2.2 system to one that incorporates the N.F.C. system. Once the N.F.C. system has been activated, the shaft register cards control the cutter and drop operations. Should a mix of necks on/off be needed in a set of drops, then use can be made of the cutter isolation switch on the shift register cards which will inhibit the cutter operation for that drop.

The rack contains the 5V regulator that powers the Shift Register Cards, whilst the relay card operates from the 24VDC source. The basic operation of the system on a card by card basis is described in the technical description section. The N.F.C. system is activated at the Relay card by turning on a switch on the front panel. When it is activated a green LED will come on. ^•

When the' system is first turned on, the relay cards will switch in new sensors. As these new sensors are placed in different physical positions on the line there will be a sensor fault registered by the CHICKWAY. The fault will be registered immediately and may remain until the reference weight passes from the weight cell to the new sensor.

The other function that the relay card performs is to switch the solenoid coils to the shift register card outputs. The CHICKWAY outputs are wired into the shift register inputs directly so there will always be inputs to the shift register cards via the opto-isolator inputs independent of the activate switch. The shift register index and half-index sensors are conditioned by the circuitry or the relay cards'. The Take Away Food (TAF) section is controlled by one relay card, as is the boning room. Another section named the KFC requires two "relay cards - basically because only one sensor conditioning circuit has been assembled on all the relay cards except for the TAF area, which is fully equipped.

The drop signals that come from the CHICKWAY are captured by the shift register cards and are indexed along by the shift register sensor. The amount of "delay" is controlled by BCD switches. The minimum index shift for the cut registers is 2 (this is because there are two shift registers controlling the cut "delay"). The minimum "delay" for the drop indexing is three. There are two groups of index delays. The signal goes into the shift card to the cut registers and comes out after the dialed delay and goes to the cut solenoid and also to the input of the drop registers. After the dialed delay the signal comes out of the drop registers through a monostable to the actual drop solenoid. If it is required to switch back to the standard CHICKWAY system when there are still birds on the line, it must_^be remembered that the shift registers have a memory capacity. The maximum amount of birds that are stored is equal to or less than the dialed up number. The other fact to consider is that the sensor is moved further forward, so not only will there be a sensor fault but also, a group of birds have been suddenly moved forward. The system will not clear itself until the reference weight goes from the weight cell to the sensor. The most preferable way to effect the changeover is to do it when there are no birds on the line between the weight cell and the relevant area.

Details of the relay card are discussed hereunder with reference to the circuit diagram Figure 8. The card performs two basic operations. It switches over the sensors and solenoid to enable the N.F.C. system to operate, and also provides conditioning circuitry to process raw sensor signals into an appropriate level for the shift register cards. The card has some options which may or may not be supplied, depending upon the particular installation requirement. The relay cards have SW3 and SWl linked (i.e. normally closed) . This means power on/off is directly controlled externally. LK3 is inserted if the relays are to be operated from one switch SW2. With this arrangement LEDs 5 and 3 will not be needed. The card generates 12V (ICl) and 5V (IC2) internally which are used in the sensor conditioning circuitry.

There is provision for two sensor conditioning circuitry, sensor A and sensor B. Should they not be required, links LK2 and LKl should be left open. The two conditioning circuits are identical so a description of only one will be given. Sensor A conditioning circuit relates to IC3 and TR2 while B relates to IC4 and TR3. The description given will be of sensor B. The input to the circuit goes through a low pass filtering network formed by R22 and C12. IC4(b) acts as a comparator comparing the filtered input with a reference value. This reference value determines the pulse width of the resulting clock. It should be adjusted (via RV3) to be half the value of voltage of the sensor O/P from when the sensor is sensing a shackle to when it is not. The output from IC4(b) is buffered by IC4a. IC4(a) drives TR3 and it is TR3 which provides the TTL output levels required by the shift register circuit. Protection for reversal of power to the relay card is achieved by D4. D4 also serves to stop any voltage surges going back out.

The shift register cards are discussed hereunder with reference -to the circuit diagram Figure 9.

The shift register cards consist of five sections:- Input conditioning

Input latching

Shift registers

Shift programming

Output circuitry. The inputs can either be TTL levels or opto-isolated input, capable of being driven from the CW2.2 directly at the higher voltage levels. IC's 7, 17 and 12 are the opto inputs with the options of being driven from an external source, or being biased from either the 24V or 5V and driven from an open collector driver or switch contact. The output from these opto inputs are then buffered by IC6 and fed into the latching circuit. The processing of the shift register "clock" or "index" signal is considered first. The sensor for the indexing of the electrical signals, through the shift registers is conditioned to give TTL level output by either one of the following: the relay card, chain stretch compensator or external circuitry. The input is presented to the card via card edge 4a, 18a. The linking options just after IC6 are provided to enable the correct signal phasing sense. As it is, the relay card and chain stretch compensator perform an inversion which can be easily corrected by the linking arrangement. IC's.3, 5 and 10 are the latches while IC16 is their clock oscillator. When the index sensor senses a shackle the level at 4a is a logic "0" (OV) , the inversion occurs at LKl point A, which is then fed into IC3b.

The signals is latched by IC3b at its Q output, pin 15, is set high. This signal then enables IC4c and IC9d. IC4c, when enabled, waits for the shackle to pass the sensor when it will receive a logic "1". IC.4c will then latch IC3a causing its Q output to go high. With IC9d enabled, and IC3a set high, IC9d will go high. ICOd's output goes through a delay network consisting of Dl, RV3, R39, and Cl. This delay network controls the Shift Register Clock width. When Cl changes to a high level, IC9c will go high and reset IC3b. When IC3b^'is reset, its output goes low and via the not Q of IC3b will also reset IC3a which also brings its Q output low. The clock signal is the Q output of IC3a, so the delay network controls the width of the Q output of IC3a. This output goes to the shift registers and the output circuitry. The pulse width should be set up in the range 40 to 60 ms. Since each shift register card runs one solenoid independently, any variation in this clock width may cause a difference to the striking position on the flipper.

The data input is derived from the opto-isolator IC17. The reason for this is to allow the CHICKWAY to operate as if the opto-was a solenoid, since the CHICKWAY output is switched to the opto input via the relay card, the arrangement is similar to the standard C.W. configuration. The data signal comes in via LK2, C to B which goes to the latch IC5b. When a data signal is sensed IC5b will go high. This signal goes to the input of the shift registers, IC5b also configures IC5a inputs to reset IC5b. This reset function is enabled by IC4b and begins when the "clock" pulse to the shift registers is produced. So, the clock pulse enables the logically inverted data signal to reset IC4a, a propogation delay later Q of IC5a goes high, setting a reset condition to IC5b via pin 12, after this it propogates through the latch, the output changes states. As can be deduced from this operation, the ^■ hold times for the data signal is produced from the propogation delays of IC5a and b.

The sequencing of the "clock" and "data" pulses are inherent in the organizing of the respective latches.

Briefly, the clock producing latches initiates a clock pulse after the shackle has passed the sensor, whilst the data becomes stable when the shackle is approximately in the middle of the sensor. The hold time, for the data signal after the leading edge of the clock has occurred, is controlled by the clock pulse'width and the propogation delays IC5a and b.

The h index signal sensor is conditioned by the relay card and enters the card via 20a,c. The signal is buffered by IC6 and is brought to IClOb where it is latched. When IClOb Q goes high it enables ICl5a (this gates the cut signal to ICl5a ready to operate the cutter solenoid) . IClOb not Q goes to IClOa, configuring IClOa to give a reset pulse which occurs when the h index goes low (shackle having passed the sensor) and the index sensor is also low. Under these conditions IClOa Q goes high. This signal goes to IC9a where it is "anded" with the logically inverted H index signal. The output of.IC9a goes through a delay network consisting of D2, RV5, R40 and C7. After the delay the signal goes to IC9b which is "anded" with logically inverted "cut signal" so, if there is no other "cut" required IC9b will reset IClOb which turns off ICl5a and via IC22 also turns off the cutter solenoid.

The h index signal is the signal which extends and retracts the cutter. The output to the cutter goes via IC22 which drives TR4, switching the solenoid.

Around the solenoid output circuit is SW3-. This switch is used to isolate the cut signal presenting the cutter "operation without the need to switch back to the existing C.W. system. The advantage in this is that a clean change can be made without the disruptions of switching back. These disruptions have been indicated in the functional description section as well as in the installation section.

The linking arrangement around J is to provide a monostable or one shot pulse output to the cutter every time a cut is required. However, by configuring Jl to J3 the cutter will remain in the cut position until there are no further birds that need the cutting operation. Strapping option G allows yet another variation to the cutting operation, where a cut operation is performed on an individual basis and the h index sensoj: is used to retract the cutter. This operation is similar to the monostable operation except the cutter is retracted by the sensor rather than after a timed pulse. The cards come configured with Jl to J3 and G to 1. The drop signal comes from the shift register and goes to ICl5b where it is gated with the clock pulse. The ensuring pulse is delayed slightly by CIO and applied to the monostable IC20. This pulse triggers the monostable to produce an output pulse whose width is controlled by RV6. This should be set and maintained within the range 60 to 100 ms. Strapping option H allows the signal to be inverted if an alternative switch arrangement is used.

Both the cutting and drop solenoids have a bias control. This control can be used to set up a small current flow in the solenoid which "biases" the coil allowing a faster turn on. This bias current also assists by helping-to control the amount of voltage spikes generated during switch off. Programming the delay in the shift registers is achieved by BCD switches and a code converting EPROM. The BDC switches have unsuitable outputs to drive the registers in a simple binary mode beyond a unit delay figure of 9. So, to assists, a code conversion EPROM is used to provide the correct code from 1,2, or 3 decades of BCD switches. The shift registers have an inherent delay of 1 when "0" is programmed into them. It must be remembered that the minimum shift delay produced from the "cut" registers is two, whit that from the "drop" registers is 3. This means that the minimum shackle separation between a "cut" and the actual cutter is 2 and between the cutter and drop position is 3 shackle spacings.

It is further understood that where customers require removal of differing amounts of neck skin or require birds of differing weight ranges a number of cutting stations may be provided, each adjusted to the desired parameters. The computer cart then be programmed to ensure that a prerequisite number of birds of the exact weight have their necks cut at a particular station. The computer can also be programmed to ensure that the right birds are released from the shackle to be collected in the correct hopper. With the method and apparatus described above neck skins can be removed from the birds without the use of an additional manually operated station. It is a simple means to bolt on the cutting station to an existing line and the computer that conducts the weighing operation can be reprogrammed to effect actuation of cutting station.

Claims

_ i6THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A method of selectively removing neck skins from poultry comprising hanging each bird upside down from a weighing shackle forming part of an overhead conveyor, electrically weighing each bird by weighing the hanging bird and shackle, feeding a signal responsive to the weight and position o.f the bird into a computer, conveying each bird past the cutting station and programming the computer to feed a signal to means to actuate a cutting blade to remove the neck skins of a preselected number of birds of certain weights.

2. The method of Claim 1 comprising programming the computer .to actuate release means to drop birds of particular weights over collection bins positioned at various sites under the conveyor.

3. Apparatus for selectively removing neck skins from poultry comprising an overhead conveyor carrying a plurality of spaced weighing shackles, a bird being arranged to be hung from each shackle, means to weigh each bird whilst hanging from the shackle, means to send a signal responsive to the weight and position of the bird, a computer programmed to store .the signal responsive to the weight and position of each bird, and a cutting blade assembly displaceable to a position across the path of the neck skins of the birds as they travel along the conveyor, whereby in use the computer sends a signal to the cutting blade assembly to displace that assembly to the cutting position as a bird of preselected weight passes the cutting blade assembly.

4. Apparatus according to Claim 3 wherein each bird is hung upside down on the shackle, each shackle having an actuatable release means so that, in use, the computer can send a signal to the release means to cause the shackle to release the bird which is collected in a bin positioned under the conveyor.

5. Apparatus according to either Claim 3 or Claim 4 wherein the means to weigh the bird comprises a load cell positioned on the conveyor rail.

6. Apparatus according to anyone of Claims 3 to 5 wherein the cutting blade assembly comprises a rotatable cutting blade pivotable about a frame and means to pivot the blade to and from an operative position where the blade is positioned across the path of the neck skins and an inoperative position in which the blade does not cross the path of the neck skins.

7. Apparatus according to Claim 6 wherein a pair of parallel guides are positioned adjacent the cutting blade assembly to guide the neck skins of the birds as they move past the cutting blade.

8. Apparatus according to either Claim 6 or 7 wherein the cutting blade rotates in a horizontal plane and the tip of the blade when in the operative position extends into a horizontal slot provided in a plastics block mount.ed on a stationary component of the conveyor, the location of the tip of the blade in the plastics block having the effect of preventing the neck skin of a bird being displaced out of the path of „the cutting blade.

9. A method of selectively removing neck skins from poultry substantially as described herein with reference to and as illustrated in the accompanying drawings.

10. Apparatus for selectively removing neck skins from poultry substantially as described herein with reference to and as illustrated in the accompanying drawings.